1. Field of the Invention
The invention relates to a rehabilitation system and method in which the appendage of a human being is first diagnosed by a data gathering mechanism and then rehabilitated through the use of virtual reality and a force feedback device such as a force feedback glove.
2. Description of the Related Art
It is known that a computer based evaluation system can be used for measuring various physical parameters of a patient's anatomy. U.S. Pat. No. 4,922,925 describes an upper extremity evaluation system including a computer directly connected to a three dimensional position locator. A pointer or wand is brought into contact with the body part for measuring the angles of maximum flexion and extension of distal segments at the joints in the fingers of the hand. Data from the position locator is entered and stored in the computer. Range of motion is calculated from the data stored in the computer. However, the drawback of this device is that the device does not provide instruction and feedback to a patient during rehabilitation therapy.
Other patents directed to computer monitoring and measurement of a patient include: U.S. Pat. No. 5,005,140 to Havriluk entitled "METHOD AND APPARATUS FOR MONITORING HYDRODYNAMIC THERAPY AND EXERCISE"; U.S. Pat. No. 5,191,895 to Koltringer entitled "METHOD AND APPARATUS FOR THE DIAGNOSIS OF POLYNEUROPATHY SYNDROMES"; and U.S. Pat. No. 4,922,905 to Crandall, et al. entitled "COMPUTER BASED UPPER EXTREMITY EVALUATION SYSTEM". Systems for clinical hand measurements are also manufactured by Exos,Inc., 8 Blanchard Road, Burlington, Mass. 01823 as the Exos Clinical HandMaster System.TM. and Greenleaf Medical, 2248 Park Blvd., Palo Alto, Calif. 94306 as Compact EVAL. The above patents provided limited data measurements related to human appendage positioning.
Interactive devices have been described to provide more accurate data measurements of the positioning of a human appendage in order to interface and control robotic functions. An example of an interactive device is the DataGlove.TM. developed by VPL Research, Inc., 950 Tower Lane, 14th Floor, Foster City, Calif. 94404. DataGlove.TM. translates hand and finger movements into electrical signals to control a remote robot. Sensor gloves such as the DataGlove.TM. typically include fiber optic sensors that are located on the back of the glove such that movement of the fingers is sensed by the fiber optic sensors and transmitted though fiber optic bundle of cables to a glove interface.
U.S. Pat. No. 5,184,009 relates to a real time optical attenuation measurement system for improving response time of a sensing glove. The system obtains signals proportional to movement of a body part to which it is attached. A light source transmits light into a conduit and the emitted light is detected at the other end of the conduit. The relative displacement of the fiber optic cable to the light source produces a signal which is converted into an electrical signal. This system is used on an operator's hand to detect movement of the hand and fingers for controlling a robotic hand which mimics the operator's hand movements.
The use of a data glove for hand evaluation was described by Wise, et al., in the Journal of Rehabilitation Research and Development, Volume 27, November, 1990, pp 411-424. Measurements were taken after a person squeezed a plaster mold for determine the force asserted by the person on the mold. It was determined that a Data Glove.TM. could be used as a semi-automated goniometric measuring device for hand range of motion (ROM) evaluation.
Other examples of sensing and measuring systems for the fingers include U.S. Pat. No. 4,986,280 to Marcus, et al. which describe a system for measuring the angular orientation of a human joint or angular finger movement; and, U.S. Pat. Nos. 4,972,024 and 5,184,009 which relate to a control system for sensing human finger movements. Sensing gloves and open loop measuring devices have the disadvantage that they lack the ability to bring force feedback to the operator's hand.
U.S. Pat. No. 5,143,505 ('505 patent), issued to G. Burdea, one of the inventors of this disclosure, describes an actuator system for providing force feedback to a dextrous master glove. An actuator for each digit receives input from sensors mounted on the glove. The actuator is a pneumatic cylinder for providing pressure feedback to the hand. A sphere joint permits rotation of the joints in a cone of about 60.degree.. The system can be used in a virtual reality environment to provide artificial force feedback in response to a pseudo environment generated by a graphics workstation and host computer. In the virtual reality environment the force feedback system interacts with a host computer. The host computer provides input to a graphics workstation which on appropriate instructions, controls a pseudo robot slave hand or a module of a human hand and pseudo virtual objects. In response to the virtual reality environment, the feedback glove applies pressure to digits. The concept of employing pneumatic cylinders, such as are described in the '391 patent, to convey force information to the patient for diagnostic and rehabilitation of hand and wrist after surgery has been described in an article in the "Engineering News" (UK) dated December 1991.
U.S. Pat. No. 5,184,319 describes a non-machine interface for measuring body part positions and providing force and texture feedback to a user. A glove is capable of sensing digit and hand positions and exerting varied forces to each digit. The interface can be used with virtual or physical objects. This patent teaches that the force and texture feedback system can be used for telemanipulation, interactive 3-D graphics and Computer Aided Design (CAD).
Of general relevance are U.S. Pat. Nos. 4,414,984 to Zarudiansky; 5,086,785 to Gentile, et al.; 5,163,228 to Edwards, et al.; and, 5,165,897 to Johnson.
The foregoing examples illustrate prior art attempts for either measuring the position and force of the fingers or providing force feedback to the fingers. However, the inventors are unaware of any practical system which has yet been devised for providing a unified computerized diagnostic and rehabilitation system for a patient using data gathering and force feedback in virtual environment.